I did two things to my Pre2 yesterday, added a few patches from Preware and dropped it in the parking lot. Today I noticed that while making a phone call the speaker does not work and the prox sensor does not disable the screen. Turning the speaker phone on works fine still The first thing I thought about was dropping it and I was ready to kick myself for breaking it. That is until I discovered the interactive tests program and to my surprise the phone's speaker and prox sensor still work perfectly fine, just not with the phone application.

I erased all the patches I had installed, did a luna restart, but still no dice. I have done all the different restarts, still nothing.

Anything else I could try before I doctor it? Such as terminal commands.

The original Pre headphone jack gets broken with regular use. The symptoms are that the phone "thinks" a headphone is plugged in when not. I've had the same thing happen once already on my Pre 2. I use the headphone jack every day.

If this is your problem, you will see the headphone symbol at the bottom of your phone screen even when no headphone is plugged in. The only solution is to replace the phone, which I've done 3 times now.

Thank you for the response, but I think you misunderstand. The speaker works fine, as in the speaker on the back. The one I'm having trouble with is the actual headset speaker. It works but it just isn't getting incoming audio during a phone call, in other words, the only time it needs to work.

Yep, I was talking about the headset speaker. The one you put against your ear when using the phone as a phone.

With nothing plugged into the headphone jack, open the phone app, then hit the voicemail button. What symbol do you see in the lower left? If it looks like a phone handset, then your headphone jack is ok. If it looks like a set of headphones, your headphone jack is jammed.

I've periodically seen this kind of issue on my phones going back to the Treos. What fixes it for me every time is a little WD-40. Spray just a little bit on your headphone 2.5mm jack plug and plug it in and out of your phone a few time, maybe rotating it a bit. I think it just dislodges some lint or something that get's in there.
I think I first leaned this trick from the old Palm forums.